I set-up a new PETG filament roll. Not sure if it’s that the filament is not sticking or the flow is bad. Can anyone say why this is malfunctioning (see photo)?
PETG HF? Did you dry it?
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DID you make sure to clean the print bed?
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No. It didn’t feel wet, but it is opened this morning. Does it dry passively through evaporation, or do I need to do something?
Not sure what HF is.
Thanks.
im thinking the bed needs cleaned since the prime line laid down fine
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HF is “high flow” it’s filament that theoretically can print faster than regular filament. You won’t know if filament is wet by feel, and often filament comes from the factory with too much moisture.
But as others have said I would take that build plate to the sink and scrub the heck out of it with dish soap and water, rinse it good and dry it with something lint free.
See if that works and if not we can talk about drying strategies.
It won’t feel wet but PETG HF is known for showing moisture issues.
The PETG HF I’ve gotten from Bambu showed moisture effects straight out of the sealed shipping bag. A good drying fixed it right up.
I’ll go out on a limb and bet your issues are moisture related.
Failed to print. Not sure if from the filament that stuck and did not reveals the cause. I did clean the plate gain but didn’t get much improvement.
what is the STL youre trying to print? Maybe it needs supports, or brim?!
The STL is 1 I have used multiple times.
good to know. well, good luck 
There is a guy come to a doctor
Guy: Doctor, my belly hurts.
Doctor: Did you eat something bad?
Guy: No, I ate the same thing I’ve eaten for long time.
…
Doctor: Good to know. Well, good luck
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If the filament is just left out, how long does drying take?
Thanks.
If filament is just left out? Like on a counter or open storage?
It depends on ambient humidity. It can very slow lose water to fairly quickly gain water.
The only way I know to be sure filament is dry is to weigh it, dry it for a period of time, weigh it, dry it some more, weigh it, and repeat until the spool stops losing weight.
You can dry filament with an X1C or P1S. It’s not great, because it ties up your printer, but it is effective, only requires an empty spool box, and will eliminate a possible cause of you troubles.
Since you do not know how much moisture is present at the start, guidelines that say “dry at X degrees for Y hours” are only very rough estimates. Without a scale accurate to a gram, follow the guide but be prepared to dry some more if results improve but some problems remain.
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Filament will not dry at all if it is “just left out” as the reason it gets wet is that it will absorb moisture from the air. To put it another way, leaving it out is what causes it to get wet.
It actually can dry in open storage. It just depends on the moisture content of the filament and the ambient humidity. And it will be slow at room temperature.
The reason is moisture-humidity curves. Put filament in a closed and impervious container and it will either absorb moisture from the air until it equilibrates, or give up moisture to the air until it equilibrates. But every humidity level has a specific moisture content in a particular kind of filament.
This is why there is a way to “know” moisture content of filament without weighing it. Only thing is it takes special equipment to measure moisture content directly but we can measure it indirectly with humidity.
Just put a spool of filament in an impervious container - poly cereal box, Ziplock freezer bag, etc - with a hygrometer, seal it, and let it sit for 10-12 hours. The humidity you measure will be set by filament moisture content.
We don’t know that moisture content but with experience, we can learn what humidities are too high for good printing. Here’s why it works - these are curves for common desiccants (filament is similar). The important point is the curves are monotonic - each humidity has a specific moisture and there are no duplicates. Each curve shows increasing moisture content with increasing humidity. These kinds of curves are characteristic of materials. So even if we don’t know the absolute moisture content, if we know humidity we have determined the moisture content even if we don’t actually know the true value. We just use humidities instead to decide if filament is dry enough.
Back to the original point, museums and archivists use desiccants for other purposes besides drying. Because of that relationship between moisture content and humidity, they condition desiccants to desired humidity levels and put them into display cases and other storage. If the humidity in a case is too low, the desiccant gives up moisture because the ambient humidity is lower than the humidity it was conditioned to. If the case has higher humidity, the desiccant absorbs moisture to try to bring it back down.
It’s a balance. An equilibrium. Since filament behaves the same, if it was at some humidity in the storage bag and you take it out and set it on a shelf in another humidity the filament will either absorb or give off water until it is at equilibrium with the ambient humidity again. Giving off is slow. Absorbing is faster, but it will do one or the other until it is in balance with its environment.
What it does - absorb or give off water - just depends on whether the air is more or less humid than the filament’s characteristic humidity set by its moisture content.
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Will try to figure out a way to lower moisture. In the meantime, here are some photos of my latest effort to print. Do they add any further data on what is happening? Seems it is not 1 area with an issue.
There is a guy come to a doctor
Guy: Doctor, my belly hurts.
Doctor: What exactly did you eat?
Guy: I ate the same thing I’ve eaten for long time.
…
Doctor: Good to know… Well, good luck…
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It’s easy to kind of ignore what people are saying when it doesn’t feel like it could matter. I am guilty of this automatic reaction myself despite trying to police myself about it. It’s human nature. Dry the filament. That’s the problem. PETG will become too moist to print properly within hours if it’s humid enough.
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